Slide 11 of 100
The aerospace transportation industry grew by leaps and bounds during the 1960s as bigger,
faster and ever more capable aircraft and rockets became available. There appeared to be no
limits to progress. In April 1963, NASA's Manned Spaceflight Center released a launch forecast
for ”Nova”-class heavy rockets in the 500-tonne payload class. The expected need for such
vehicles in 1975-90 included a 50-crew Moonbase (1975-), manned Mars flights (1981-), unmanned
planetary craft (1979-), large space stations (1980-),and a "global transportation system"
(1980) with 242 flights/year by 1990, and a “Nova military strike force” in 1976
(15 flights/year by 1981). Douglas Missile & Space Systems tried to capitalize on this by
proposing a series of suborbital rockets capable of transporting 110-260 passengers at
25,000km/h. The “Hyperion” vehicle was truly remarkable since it would have been
launched horizontally and landed vertically (HTVL) -- an extremely rare combination. The payload
capability was 110 passengers or 18t of cargo. The
takeoff mode was similar to contemporary HTHL TSTOs, I.e. a subsonic sled riding on a cushion
of air. Hyperion would be travelling at 1100km/h as it leaves the sled at the end of the 3km
launch rail. Unlike other Douglas SSTO concepts, Hyperion was fully reusable so it would have
been ideally suited for flights from inland sites since no fuel tanks would be dropped during
flight. The booster sled would literally have provided a “flying start” which greatly reduced
the SSTO dry mass. Unfortunately, the Hyperion launch system also required a 1.7km high
mountain so Douglas mostly regarded the concept as an experimental vehicle.
Douglas expected that the vehicle would cost $1.5 billion to develop (=$8 billion at 1999 economic
conditions), and the cost per seat would have been $3000 -- or $15000-16000 in 1999.
"Frontiers of Space" -- Phil Bono and Kenneth Gatland, 1969.